I did the same in July 2012. It took me about 4 months to get back on a bike, fully padded up. Initially it was just riding local bridleways etc, as I was worried about falling off etc. It took me about 1 month of that and some very understanding mates (as I was stopping and scared of anything remotely technical) to ride trail centres. About a month after that I started riding the natural stuff (Peaks) again.
As Ciron says the key thing is to get it moving as early as possible.
I’ve lost about 20 degrees of movement in total, which was due to me making a right mess of the elbow (it smashed into 7 pieces, one of which went missing when I fell off). The Doc who did the second op (I had to have it reworked due to the wires and pins being the wrong size) said the best he was hoping for was a loss of around 40 degrees.
I was spending about 2 hours a day working my elbow for 2 months, to try and get it back. It hurt and felt funny but I think it was worth it. Even now I still do the exercises.
Good luck.